The present invention relates to a supporting framework for a control cabinet including several geometrically distinct structural elements. In particular, the framework comprises side frame elements that are hollow and open to the interior of the cabinet, and cross-beam elements for connecting the side frame elements to each other. Tracks of punched holes are provided on each type of element for mounting cover panels, doors and built-in components.
The prior art discloses several supporting frameworks of various types. In German Pat. No. DE-C 26 27 260, the supporting framework is composed of individual sections of a single type. This common element is used both for the side frames and the cross-beams connecting the side frames. Separate corner pieces are used to provide fixed screw connections between the elements. Another prior art patent (German Pat. No. DE-A-16 65 984) discloses the use of tracks of holes and structural members. However, the elements used in this device are large and heavy. The combination of side frame parts cross-beams is known in the prior art (DE-C-22 14 538). Other types of prior art devices have been proposed as well (DE-B-11 91 454).
The load bearing capacity of the prior art frameworks is limited. In particular, when one builds such cabinets beyond certain ratios of height to width and height to depth, structural deformations and vibrations tend to occur. To counteract such harmful effects, the structural elements employed must be scaled up in size, particularly, in cross-sectional size. While using thicker elements does enhance the load bearing capacity of such structures, it also greatly increases the structure's weight, thereby making them uneconomical to mass produce. Furthermore, the basic suitability of a supporting framework can also be adversely effected when using structural elements that are very thick, have a large cross section, or require many reinforcements.
Hence, there remains a need for a supporting framework for a control cabinet that is light, requires few materials, is stable, and is suited for mounting a wide range of built in components. Such a device should offer ease of connection to other identical control cabinets, as well as easily accessible mounting and connection points.